diff --git a/openbsc/src/input/lapd.h b/openbsc/src/input/lapd.h
index 73195d6..671fd90 100644
--- a/openbsc/src/input/lapd.h
+++ b/openbsc/src/input/lapd.h
@@ -8,6 +8,7 @@
 	LAPD_MPH_DEACTIVATE_IND,
 
 	LAPD_DL_DATA_IND,
+	LAPD_DL_UNITDATA_IND,
 
 } lapd_mph_type;